Well do we really want to know what "they" are doing to protect us? The DHS, CIA, et.al. don't have to tell the public and media about counter-terrorism stuff. They work in the shadows. Isn't that what we want them to do, to protect us while we're sleeping? Why does the media feel the need talk about it? Wouldn't it undermine the anti-terorist programs by broadcasting them?

I know it's cliche to say, but what does it tell you about the job the DHS, CIA, etc. is doing that we haven't had a terrorist succeed in a large-scale destructive act in the U.S. since 2001? Id say they are doing a great job!

Posted By xtina - chicago IL : 4:18 PM ET

David,I certainly hope that the edge of disaster segment helps us to caulk the cracks that could be penetrated instead of revealing vulnerable locations to those who wish us harm. Cheers to all of you at 360 and especially those rebuilding and celebrating Fat Tuesday in New Orleans. I think I'll need to pour a glass of wine just to view what is NOT being done to protect us. At midnight I'll give up my wine for lent which also means I may have to give up turning on the news until Easter. Nah, I can't give up both, just the wine!

Posted By Betty Ann, Nacogdoches TX : 4:27 PM ET

In today's world the edge of disaster is always too close to home. I'm in small town rural America yet living in a university town and with the mix of cultures and ethnic groups I believe there is always the possibility for trouble. Isn't it a sad day when we have to stress over attending a ball game or concert because the ever present question in the back of mind is haunting us. When is next the 911? Where will it take place this time? Could it affect me or my family? I suppose to some degree we all live with these quesstions. I'm sure Stephen's book isn't a good bedtime read however it brings reality into the American psyche and shares a dose of what could come. We all need to filter through our hometowns and consider what we would do if "disaster" struck in our area. Preparation is half the battle of surviving any kind of threat or attack. Thanks Stephen for shedding new light on what could happen to us. Let it be a reminder to keep our guard up and our eyes open.

Posted By Zann Martin, Tennessee : 5:25 PM ET

Dear David,

Hi, great post and video! Maybe some of the most vulnerable states and cities should have a disaster expert on staff; it wouldn't hurt if that expert had an imagination as well. As I recall, Tom Clancy foreshadowed the type of attack that took place on 9/11 in his novel "Debt of Honor (1994)," and even Chris Carter included such an attack in the premiere episode of "The Lone Gunmen" on March 4, 200l.

It would help if the officials of cities like New Orleans would make sure that their levees and other protective structures were adequately secure and update them on a regular basis rather than waiting for them to fail before addressing the problem. A workable evacuation plan would be useful as well.

It is difficult for some of us who don't live in a high risk area to understand the feelings of people like Josephine Butler, but we should be sympathetic and try to understand what it would be like to live somewhere for so many years and then be forced to leave everything behind. I wish her and the other residents of the Ninth Ward the best of luck; they certainly deserve it.

I will not be surprised to learn how little is being done to prevent these threats. It is difficult to believe that our cities and states are unaware of their vulnerabilities. Most are unwilling or unable to do anything about them because of the amount of funding it would entail. They are just crossing their fingers and hoping for the best.

Some people say that by revealing these weaknesses we are enabling the terrorists, however, I believe that the citizens of this country are entitled to some information that they can use to save their lives and property.

I look forward to tonight's program; it is a subject we should all take an interest in.

Take care, Jo Ann

Posted By Jo Ann Matese, North Royalton, Ohio : 5:42 PM ET

David/AC360:Every Memorial Day, when thousands of individuals stuff themselves into the Indianapolis Motor Speedway and the Goodyear blimp is visiting overhead, the local press does not usually talk about what to do in a terrorist attack at the Speedway.

But I do remember one time when a tornado warning came over the loud speaker. Basically, people stayed. What were the "odds" that a tornado would touch down and hit the 2 and half mile track surrounded by bleachers and corporate suites?

Anyway, a panicked crowd would cause mass hysteria. It can take hours just to get out of the Speedway to find your car.

I believe the city of Indianapolis does have emergency procedures. They have to.....it is an annual event and an American institution.

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